Answer
a) $C=+200x$
b) $R=450x$
c) 200 desks are produced and sold
Work Step by Step
Let's note by $x$ the number of desks.
a) The cost $C$ contains the fixed cost and the cost of the $x$ desks:
$C=60000+200x$
b) The revenue $R$ is the amount got from selling $x$ desks:
$R=450x$
c) The break-even point happens when cost equals revenue:
$C=R$
$60000+200x=450x$
$60000+200x-200x=450x-200x$
$60000=250x$
$x=\dfrac{60000}{250}$
$x=240$ desks
